Which elements are most abundant in the sun?

• A. Hydrogen and Helium
• B. Oxygen and Carbon
• C. Iron and Nickel
• D. Neon and Argon

Answer: (A)

Hydrogen and helium are the most abundant elements in the Sun. About three-quarters of the Sun’s mass is hydrogen, and roughly one-quarter is helium, with only a tiny fraction made up of heavier elements. This pattern comes from the Sun’s origin in a cloudy solar nebula and is supported by analyzing the solar spectrum, which shows strong signatures of hydrogen and helium, as well as by models of stellar composition. The Sun’s energy comes from hydrogen nuclei fusing into helium in its core, which aligns with having so much hydrogen available. The other elements—oxygen, carbon, iron, nickel, neon, argon, and the like—exist in much smaller amounts, so they are not as abundant as hydrogen and helium.